In order to keep up with the increased demand for computer applications, computer application developers have created tools to help in the development of computer programs, such as visual builder tools or application builder tools. These tools generally include standard sets of software modules that may be interlinked to create custom-built applications.
One such widely used object-oriented visual builder tool is Visual Basic available from Microsoft Corporation of Redmond, Wash. Visual Basic has a graphical user interface (GUI) that facilitates the development of computer applications, such as database access applications. The GUI includes a “toolbox,” a “form window,” and a “property sheet.” A toolbox typically contains icons or text which represent different classes of components or software modules. An example of different classes may include complex components (e.g., database viewers) and simple components (e.g., buttons). An application may be composed in the form window by selecting a component from the toolbox and placing it within the form window. A developer graphically composes an application by interlinking components in the form window. The components are interlinked based on properties or attributes relating to the selected component as displayed in the property sheet. The properties may include information relating to the size, color, and name of the selected component.
Many Visual Basic developers have substantial experience with two tier environments that involve applications for direct querying or access to a database. In a two tier environment, a client computer system (first tier) directly communicates with a database system (second tier) to access data. The second tier is often a relational database that uses Structured Query Language (SQL) as the protocol language for communicating with other systems.
With the advent of the Internet and the use of application servers, three tier environments are becoming more popular. In a three tier environment, a client system (first tier) has a GUI that communicates with an application running on an application server (second tier) which in turn communicates with a database server (third tier) for access to and storage of data. Because three tier environments enable business applications on the second tier to be modified without having to substantially modify each client system, a three tier environment may be more efficiently: maintained and updated than a two tier environment that generally requires each client application to be modified when changes are desired. This advantage of the three tier environment has made many businesses consider switching to three tier systems.
One consideration businesses take into account when switching to different computer systems is the cost of training required for the developers and technical staff. For companies that have a significant number of developers trained only in two tier system language protocols, switching to a three tier environment may result in these developers not being able to use many of their previously learned skills. As a consequence, many businesses may be reluctant to switch to a three tier environment due to training time and cost concerns. Furthermore, programmers may be reluctant to learn a new computer language. For example, these developers may not be versed in the Java™ programming language which is becoming the standard in many three tier environments. The Java™ programming language is suited for use in a three tier environment due to programming conventions such as Java™ Beans (JB) and Enterprise Java™ Beans (EJB). EJB components may link other EJB components or may be designed to perform customized operations when invoked or called.
Some conventional systems enable applications, such as Visual Basic applications, to operate in conjunction with a three tier environment. However, these systems require the Visual Basic application developer to learn a complex protocol interface language, such as DCOM, to interact with an application or middle tier server. Consequently, these application developers may be reluctant to learn a complex protocol interface language in order to develop applications that operate in a three tier environment. Given the existing skill base for programming in two tier environments, there is a need for a method and system that enables computer program developers to continue to use their existing two tier skills in a three tier environment, without learning new computer programming protocols or languages.